org.kalypso.gmlschema.types.SimpleDOMTypeHandler.java Source code

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Here is the source code for org.kalypso.gmlschema.types.SimpleDOMTypeHandler.java

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/*----------------    FILE HEADER KALYPSO ------------------------------------------
 *
 *  This file is part of kalypso.
 *  Copyright (C) 2004 by:
 *
 *  Technical University Hamburg-Harburg (TUHH)
 *  Institute of River and coastal engineering
 *  Denickestrae 22
 *  21073 Hamburg, Germany
 *  http://www.tuhh.de/wb
 *
 *  and
 *
 *  Bjoernsen Consulting Engineers (BCE)
 *  Maria Trost 3
 *  56070 Koblenz, Germany
 *  http://www.bjoernsen.de
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 *  Contact:
 *
 *  E-Mail:
 *  belger@bjoernsen.de
 *  schlienger@bjoernsen.de
 *  v.doemming@tuhh.de
 *
 *  ---------------------------------------------------------------------------*/
package org.kalypso.gmlschema.types;

import java.io.StringReader;
import java.io.StringWriter;
import java.net.URL;
import java.text.ParseException;

import javax.xml.namespace.QName;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.apache.commons.io.IOUtils;
import org.kalypso.contribs.java.xml.XMLHelper;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
import org.xml.sax.XMLReader;

/**
 * A simple DOM serializer. May be subclassed.
 *
 * @author schlienger
 */
public abstract class SimpleDOMTypeHandler implements IMarshallingTypeHandler {
    private final QName m_qname;

    private final boolean m_isGeometry;

    public SimpleDOMTypeHandler(final QName qName, final boolean isGeometry) {
        m_qname = qName;
        m_isGeometry = isGeometry;
    }

    @Override
    public void marshal(final Object value, final XMLReader reader, final URL context, final String gmlVersion)
            throws SAXException {
        try {
            final DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
            final DocumentBuilder builder = factory.newDocumentBuilder();
            final Document document = builder.newDocument();
            final Node node = internalMarshall(value, document, context);

            // value is encoded in xml in document object
            final StringWriter writer = new StringWriter();
            XMLHelper.writeDOM(node, "UTF-8", writer); //$NON-NLS-1$
            IOUtils.closeQuietly(writer);

            // value is encoded in string
            final String xmlString = writer.toString();
            final InputSource input = new InputSource(new StringReader(xmlString));
            final SAXParserFactory saxFac = SAXParserFactory.newInstance();
            saxFac.setNamespaceAware(true);

            final SAXParser saxParser = saxFac.newSAXParser();
            final XMLReader xmlReader = saxParser.getXMLReader();
            xmlReader.setContentHandler(reader.getContentHandler());
            xmlReader.parse(input);
        } catch (final SAXException saxe) {
            throw saxe;
        } catch (final Exception e) {
            throw new SAXException(e);
        }
    }

    protected abstract Node internalMarshall(final Object value, final Document document, final URL context)
            throws TypeRegistryException;

    @Override
    public void unmarshal(final XMLReader reader, final URL context, final UnmarshallResultEater marshalResultEater,
            final String gmlVersion) throws TypeRegistryException {
        try {
            final UnmarshallResultEater eater = new UnmarshallResultEater() {
                @Override
                public void unmarshallSuccesful(final Object value) throws SAXParseException {
                    final Node node = (Node) value;
                    if (node == null)
                        marshalResultEater.unmarshallSuccesful(null);
                    else {
                        try {
                            final Object object = internalUnmarshall(node);
                            marshalResultEater.unmarshallSuccesful(object);
                        } catch (final TypeRegistryException e) {
                            throw new SAXParseException(e.getLocalizedMessage(), null, e);
                        }
                    }
                }
            };

            // FIXME: use transformer instead of self-made stuff

            final DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
            factory.setNamespaceAware(true);

            final DocumentBuilder builder = factory.newDocumentBuilder();
            final Document document = builder.newDocument();
            final DOMConstructor domBuilderContentHandler = new DOMConstructor(document, eater);

            // simulate property-tag for dombuilder
            reader.setContentHandler(domBuilderContentHandler);
        } catch (final Exception e) {
            throw new TypeRegistryException(e);
        }
    }

    /**
     * Subclasses may extend
     */
    @SuppressWarnings("unused")
    protected Object internalUnmarshall(final Node node) throws TypeRegistryException {
        return node;
    }

    @Override
    public Object cloneObject(final Object objectToClone, final String gmlVersion)
            throws CloneNotSupportedException {
        throw new CloneNotSupportedException();
    }

    @Override
    @SuppressWarnings("unused")
    public Object parseType(final String text) throws ParseException {
        throw new UnsupportedOperationException();
    }

    @Override
    public abstract Class<?> getValueClass();

    @Override
    public QName getTypeName() {
        return m_qname;
    }

    @Override
    public boolean isGeometry() {
        return m_isGeometry;
    }
}